Installing solar panels[4] seems pretty straightforward – just aim them south so they get lots of sun all day. But researchers are finding that we may have been doing it wrong this whole time. While studying residential solar power’s impact on the power grid, researchers at Pecan Street Research Institute[5] uncovered an unexpected result: homes with west-facing solar panels generated more power than those with conventional south-facing panels. Depending on the time of day, west-facing solar panels produced at least two percent more power and sometimes much more.

In the northern hemisphere, architects, utilities and home owners have long believed that directing solar panels to the south will give them maximum exposure to the sun because they get a bit of sun all day long. But when the Pecan Street researchers studied homes in Austin, Texas, the results showed that south-facing solar panels actually produce less energy. In the afternoon, when energy demand increases, west-facing panels generated even more power[8].

During peak hours, a typical home with solar panels in Austin reduces reliance on the power grid[9] by 54 percent. That number went up to 65 percent for homes with west-facing panels. That’s a significant power savings right when the grid needs it most. While this is just one study and further testing will be necessary to confirm the findings, there’s a chance that something as simple as shifting the angle of future PV installations could translate to significant solar power production gains.